Changed l to f in stlc to match gtlc
Changed l to f in stlc to match gtlc

akuhlens/schml,akuhlens/schml,Gradual-Typing/Grift,Gradual-Typing/Grift,akuhlens/schml,Gradual-Typing/Grift,akuhlens/schml,akuhlens/schml,akuhlens/schml,Gradual-Typing/Grift